Field
The disclosure relates to devices and methods for filtering body fluids such as blood and/or selectively deflecting potentially embolic particles from the body fluid. The devices can be catheter-based for insertion into a vascular system of a subject.
Description of Related Art
Thromboembolic disorders, such as stroke, pulmonary embolism, peripheral thrombosis, atherosclerosis, and the like affect many people. These disorders are a major cause of morbidity and mortality in the United States and throughout the world. Thromboembolic events are characterized by an occlusion of a blood vessel. The occlusion can be caused by a clot which is viscoelastic (jelly-like) and comprises platelets, fibrinogen, and other clotting proteins.
Percutaneous aortic valve replacement procedures have become popular, but stroke rates related to this procedure are between four and twenty percent. During catheter delivery and valve implantation, plaque or other material may be dislodged from the vasculature and may travel through the carotid circulation and into the brain. When an artery is occluded by a clot or other embolic material, tissue ischemia (lack of oxygen and nutrients) develops. The ischemia progresses to tissue infarction (cell death) if the occlusion persists. Infarction does not develop or is greatly limited if the flow of blood is reestablished rapidly. Failure to reestablish blood-flow can lead to the loss of limb, angina pectoris, myocardial infarction, stroke, or even death.
Reestablishing blood flow and removal of the thrombus is highly desirable. Surgical techniques and medicaments to remove or dissolve obstructing material have been developed, but exposing a subject to surgery may be traumatic and is best avoided when possible. Additionally, the use of certain devices carry risks such as the risk of dislodging foreign bodies, damaging the interior lining of the vessel as the catheter is being manipulated, blood thinning, etc.